Toilet tank



FIG. 1 is a top, front and left side perspective view of a toilet tankshowing our new design in full lines, and environmental associationmatter shown in broken lines and forms no part of the claimed design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a right side elevational view thereof;

FIG. 5 is a rear elevational view thereof;

FIG. 6 is a bottom plan view thereof; and,

FIG. 7 is a top, front and left side perspective view of an alternativeembodiment of our new design in full lines, and environmentalassociation matter shown in broken lines and forms no part of theclaimed design.

The ornamental design for a toilet tank, as shown and described.